I don’t know what a pole barn nail weighs. Most of the bo shuriken I’ve used from Japan are surprisingly heavier . There are two types of throwing techniques that are widely used when throwing Bo Shurikens or spikes. Knife Grip: Hold the Bo Shuriken by one end a so that . There are many instructables and guides for making Bo Shurikens, or what is known more commonly to Westerners as Throwing Spikes.